Brim-curling apparatus

ABSTRACT

Brim-curling equipment for plastic or like disposable cups wherein the lowermost cup in an inverted stack thereof is engaged by cooperating internal and external dies to shape the lip curl or brim of the cup to a desired rounded configuration while the stack is supported by the internal die, after which the finished lowermost cup is denested and removed from the stack by the internal die while the remainder of the stack remains supported during cup removal first by the external die and thereafter by a circumferential series of dogs for a succeeding curling operation on the next lowermost cup.

States a atent [72] Inventor William Stanley Gillespie Glen Ellyn, ill. [21] Appl. No. 879,685 [22] Filed Nov. 25, 1969 [45] Patented Jan. 4, 1972 [73] Assignee American Can Company New York, N.Y.

[54] BRlM-CURLING APPARATUS 10 Claims, 10 Drawing Figs.

[52] US. Cl 425/395, 93/365, 425/436 [51] Int. Cl B29c 17/02 [50] Field of Search 18/19 BC, 19 BE, 19 BM; 93/365; 264/322, 296, 297; 221/223, 295, 297

[5 6] References Cited UNITED STATES PATENTS 3,348,266 10/1967 Brown et al 18/19 BC 2,689,400 9/1954 Mirando 2,778,287 l/l957 Moore ABSTRACT: Brim-curling equipment for plastic, or like disposable cups wherein the lowermost cup in an inverted stack thereof is engaged by cooperating internal and external dies to shape the lip curl or brim of the cup to a desired rounded configuration while the stack is supported by the internal die, after which the finished lowermost cup is denested and removed from the stack by the internal die while the remainder of the stack remains supported during cup removal first by the external die and thereafter by a circumferential series of dogs for a succeeding curling operation on the next lowermost cup.

I PATENTEUJAN 4:972 3:632:27; sum an? INVENTOR. WILLIAM STANLEY GILLESPIE ATTORNEY BRIM-CURLING APPARATUS BACKGROUND OF THE INVENTION The advent of disposable cups of paper, plastics, and various laminates known in the art has required considerable development of tooling to effect proper brim formation on the cups so as to provide a relatively tightly curled brim not only to rigidify the cup but also to provide a comfortable feel of the cup to the lips of the user.

As an out-turned brim or lip configuration cannot be readily shaped to finished contour until the cup itself is formed, relatively complex tooling has hitherto been developed to handle individual cups of the customary frustoconical configuration and to effect proper brim shaping without damaging or breaking the cup.

Competitive conditions require, however, that brim-curling apparatus be able to achieve rapid and reliable operation in order to keep up with the demands of high-speed machinery in the mass production of disposable cups, especially with the relatively recent development of low-cost thermoformed cups of polystyrene foam.

In this connection, disposable cups of foamed plastic or like materials are normally supplied in nested stacks for ease and practicability of handling. Accordingly, brim-curling equipment and techniques must be capable of acting upon an endmost cup in the stack, and promptly remove the same from the stack so that the apparatus may then work on a subsequent cup, all with a minimal of mechanical complexity in the necessary die-shaping operation.

Also, between brim-curling operations, the stack of cups must be suitably supported in a manner which will not interfere with the successive brim-curling operations.

SUMMARY OF THE INVENTION The present invention is characterized by equipment wherein an inverted stack of cups having preformed preliminary brims requiring final brim curling and shaping are supported by yieldable dogs, which dogs pivot out of stack-supporting relation when an internal brim-forming die is advanced through the circular path defined by the dogs, and into the lowermost inverted cup, deflecting the dogs from stacksupporting relation, whereby the weight of the cup stack is thereupon transferred to and supported by the internal die.

Further, advance of the internal die effects positive cam advancement of laterally disposed external dies into cooperative brim-shaping relation to the internal die at the cup brim, whereby the brim of the lowermost cup in an inverted stack thereof is suitably shaped while the cup stack is supported on the die.

The lowermost cup is securely held to the internal die during the brim-shaping operation as by vacuum means acting through ports in the internal die.

After brim curling, the internal die retracts from the stack, bringing with it the finished cup held thereon by vacuum. Retraction of the internal die effects mechanical camming of the external brim-shaping dies away from the finished cup and cup stack.

The rate of outward movement of the external dies is such, however, that the external dies serve to temporarily support the remainder of the cup stack in their partially withdrawn position until such time as the internal die carrying the finished cup has retracted downwardly sufficiently to permit the spring dogs to spring inwardly and reengage the stack to support the same.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings illustrate a preferred form of the invention, wherein:

FIG. 1 is a top plan view of the brim-curling apparatus of the present invention;

FIG. 2 is a front elevation, partially in section, of the apparatus of FIG. 1, and partly broken away for clarity;

FIG. 3 is a side elevation of the apparatus, partly in section;

FIG. 4 is an enlarged side elevation partially in section, showing the apparatus prior to commencement of the brimcurling operation;

FIG. 5 is similar to FIG. 4, illustrating the apparatus at the completion of the brim-curling operation upon a cup;

FIG. 6 is similar to FIG. 5, showing the parts subsequent to completion of a brim-curling operation, with the completed cup partially denested from the cup stack as the lower die retracts;

FIG. 7 is a fragmentary perspective view of one of the external die portions;

FIG. 8 is a fragmentary section illustrating the relation of the internal die air passages to the discharge chute; A

FIG. 9 is a fragmentary enlarged illustration of the mating die surfaces just prior to brim curling; and

FIG. 10 is similar to FIG. 9 disclosing the die surfaces in final brim-shaping relation.

DESCRIPTION OF THE DISCLOSED EMBODIMENT Referring to the drawing, the apparatus 10 of the present inrecessed adjacent each dog for a spring 20 which normally urges the dogs 18 radially inwardly to the illustrated position of FIGS. 2 and 4, whereby the dogs support the cup stack by engagement with the undersurface of the partially formed brim .B of the lowermost cup. Suitable stop means of conventional form limit inward movement of the dogs.

Frame 12 on either side of the sleeve 14 is additionally surmounted by tubular guide members 22 over frame openings 23, the members 22 receiving guide pins 24 extending from crosshead 26. Crosshead 26 includes a central actuating rod 28 which is guided through a lower extension 12a of frame 12 (FIG. 2), the rod 28 being affixed to a suitable reciprocating motor means, such as a fluid piston and cylinder (not shown). The crosshead 26 is centrally surmounted by an internal brim-- shaping die 30 having a contoured shaping surface 32 about its upper periphery. The die 30 is secured to crosshead 26 in any suitable manner such as by capscrews 34 (FIG. 2), and the die 30 is ported as shown at 36 to permit fluid communication to the upper surfaces thereof. The internal passage 36 communicates with an external line 38, which in turn is connected by suitable flexible tubing to air suction and pressure control means of conventional nature, not shown.

Internal die 30 is so positioned to be in alignment with the cup stack within sleeve 14, whereby when the crosshead is elevated upon advancement of rod 28, internal die 30 will advance into the lowermost inverted cup as seen in FIG. 5, as will be noted more fully hereinafter.

For safety purposes, each of the tubular guides 22 includes an upstanding protective cover 39, and it will be noted that one cover is slotted at 40 to permit the projection thereinto of switch arms 41 of cycle-controlling limit switches 42 which in turn are suitably mounted upon sleeve bracket 44. The switches 42 control the fluid cylinder or other prime mover affixed to rod 28 in known manner.

The frame 12 includes upper and lower plates 46, 48 which are suitable channeled or otherwise shaped to slidably receive a pair of external brim-curling die plates 50. As seen in FIG. 7, each external die plate 50 includes a suitably contoured semicircular brim-curling surface 52. Further, each die plate is suitably apertured at 53 to receive a specially configured portion of guide pin 24 therethrough.

More particularly, each die plate 50 includes a pair of spaced complementary cams 54, 56 suitably affixed to the plate. The cams are suitably contoured to impart desired rectilinear movement to the die plate as a cam roller 58 carried by each guide pin 24 is passed vertically through the path defined by the cam pair.

To this end, each guide pin 24 in the area peripherally adjacent the cams 54, 56 is transversely relieved as best seen in FIG. to provide an axle pin mounting 66 for a cam roller 58. Further, the pins are longitudinally relieved on either side of roller 58 to form outwardly facing grooves at 62, 64 within which the cam members 54, 56 are respectively received as the guide pins reciprocate between the cams 54, 56, as is quite clearly evident from FIG. 4.

It is therefore evident that as the crosshead 26 advances from the FIG. 4 to the FIG. 5 position, the cam rollers 58 will pass between the earns 54, 56 causing the latter to shift in accordance with the contoured path defined therebetween as the rollers 58 pass rectilinearly upwardly as constrained by guides 22, whereupon the external dies 50 will be cammed laterally inwardly to the FIG. 5 brim-shaping position, and in like manner as the guide pins 24 subsequently move downwardly, cams 54, 56 will positively effect lateral outward retraction of the external dies 50 from proximity to the brim of the cup.

Also mounted upon frame 12 as by a suitable bracket 66, as seen in FIG. 3, is a discharge chute 68 which leads to a suitable collection receptacle for finished cups.

In operation, sleeve 14 is loaded with a supply of cups C in nested relation whose brims B are partially inturned in preliminary form as seen best in FIG. 9, and thereby requiring final curling and shaping operations to be performed by the subject apparatus. The stack is supported by the several dogs 18 engaging the surface of the lowermost cup brim. In one working embodiment four such dogs are provided at 90 circumferential intervals about ring 16, but it is obvious that a greater or lesser number may be used as may be found desirable or necessary.

At the time of loading, the crosshead 26 and die 30 thereon are in their lowermost position of FIG. 2. Inasmuch as the crosshead 26 is lowered and remote from cup C, external die plates 50 are likewise in similar retracted position as seen in FIG. 2.

Upon commencement of the brim curling and shaping operation, an aforediscussed prime mover, such as a piston and cylinder, advances rod 28 upwardly and thereby the crosshead 26, the same being maintained in proper alignment to the frame 12 and to the supply of cups C by virtue of the guide pins 24 slidably received within tubular guides 22. As the internal die 30 moves from the FIG. 2 to the FIG. 4 position, cam rollers 58 approach earns 54, 56.

Continuing to the FIG. 5 position, it will be evident that die 30 enters the mouth of the lowermost cup C, and as the shaping surface 32 thereof is substantially fully received within the mouth of the cup, the subjacent peripheral die surface will deflect stack-supporting dogs 18 outwardly against the force of the radially acting springs 24). The dogs 18 will then no longer support the stack, but the same will be in fully supported relation upon the die 30. Substantially at this time, a suction is applied through lines 38 and 36 to thereby positively and snugly hold the lowermost cup C on the die 30, thereby to insure proper alignment and positioning of the cup with respect to the die-shaping surface 32.

As is now evident, upward movement of the die 30 into the lowermost cup mouth likewise effects inward lateral movement of the semicircular die plates 50 under the influence of cam rollers 58 on guide rods 24 in passing from the FIG. 4 to the FIG. 5 position. The external die plates 50 are positively shifted to the FIG. 5 position just before the internal die 30 reaches its uppermost point in its travel. The movement of the internal die 30 to its uppermost position positively compresses the brim curl B against the external die plates 50, from the preliminary FIG. 9 condition to the finished rounded lip of FIG. 10. At this point, the guide pins 24 have reached the uppermost limit of their stroke and have engaged the uppermost limit switch 42, controlling timed reversal of the prime mover acting upon the crosshead, whereupon the same will descend from the FIG. 5 back to the FIG. 2 position.

During initial descent, suction is still maintained in lines 36, 38 whereby the lowermost cup with the finished brim is positively pulled downwardly with die 30, and withdrawn from the superposed cup stack. At the initial stage of withdrawal as seen in FIG. 6, lowermost cup C is partially denested from the stack, but dogs 18 have not yet been freed sufiiciently to swing in beneath the remaining stack of cups. Untoward downward movement of the nested stack at this time is, however, positively prevented by the external brim-shaping dies 50 which at this point have moved only slightly away from the brim area and still project inwardly sufficiently to engage the undersurface of the next succeeding lowermost cup C, thereby to temporarily support the stack. The precise extent and duration of this stack-supporting action on the part of cams 50 is of course determined by the particular contour on the cam surfaces 54, 56, and may be varied as requisite for cups for different shape, materials, etc. Suitable configuration, for example, can provide for a rather slow initial outward movement of the plates 50 thereby maximizing cup stack support thereby, followed by a relatively rapid outward movement as the crosshead moves lower and the cams 54, 56 change their contour at a greater rate accordingly to provide the more rapid outward movement at the part of the stroke shown in FIG. 4.

Further downward movement of the crosshead 26 causes the die 30 and the finished cup supported thereby to clear the dogs 18, which latter immediately pivot inwardly under the infiuence of the springs thereby to engage and again support the stack of cups C as the die plates 50 complete their outward retraction as aforesaid.

As the die 30 reaches its lowermost position of FIG. 2, suction in line 36 is terminated, and compressed air applied therethrough whereby the cut will be positively ejected from the die. The contour of the die passages as at 36a, 36b in FIG. 8 is preferably such that the cup is ejected laterally into discharge chute 68. Switchover of the air line from suction to compressed air as well as subsequent recommencement of the crosshead upstroke for succeeding brim-curling operations is principally controlled by the lowermost switch 42 which is actuated as the reduced end portion of guide pin 24 approaches the switch arm 41 thereof.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement of parts of the apparatus mentioned herein without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the apparatus hereinbefore described being merely a preferred embodiment.

I claim:

I. Brim-curling apparatus comprising a frame,

yieldable means carried by said frame for yieldably supporting a vertical stack of cups,

brim-shaping means carried by said frame including an internal die and an external die,

means effecting nonrotational relative motion between said dies to effect cooperative internal and external shaping and curling of the brim of the lowermost cup disposed therebetween,

and means adapted to engage said yieldable means for transferring the cup stack support function from said yieldable means directly to said dies during brim curling of said lowermost cup of said stack.

2. The brim-curling apparatus of claim I wherein said yieldable supporting means comprise a plurality of dogs mounted in said frame for outward yielding movement, said dogs being disposed in circumferential array normally to engage beneath the lowermost cup of the stack, and said means for effecting nonrotational relative motion includes means mounting said internal die for axial movement to and from the open lowermost cup mouth and through said dog array thereby to deflect said dogs outwardly.

3. The brim-curling apparatus of claim 2 including cooperating cam means between said internal die and said external die for effecting external die movement in response to axial movement of said internal die.

4. The brim-curling apparatus of claim 3 wherein said external die comprises a pair of semicircular die portions disposed in normally laterally spaced relation to each other and to the lowermost stacked cup supported by said dogs, and,

said cam means effects advancing confronting movement of said semicircular die portions into embracing brim-shaping relation about the cup periphery as said internal die enters the cup mouth.

5. The brim-curling apparatus of claim 4 wherein said internal die includes cup-holding means to retain the cup thereon during the brim curling thereof.

6. The brim-curling apparatus of claim 5 wherein said cupholding means is effective to remove the finished lowermost cup from the stack upon axial movement of said internal die from the stack.

7. The brim-curling apparatus of claim 6 wherein said cup holding means comprises a suction line acting through said internal die.

8. The brim-curling apparatus of claim 7 including means to eject a finished cup from said die.

9. The brim-curling apparatus of claim 6 wherein said cam means causes said external die portions to engage and support said cup stack during initial axial movement of said internal die and said finished cup thereon away from said stack.

10. The brim-curling apparatus of claim 4 wherein said internal die is mounted on a crosshead having guide pins slidably journaled in said frame, and,

said cam means are cooperatively associated with said external die portions and said guide pins. 

1. Brim-curling apparatus comprising a frame, yieldable means carried by said frame for yieldably supporting a vertical stack of cups, brim-shaping means carried by said frame including an internal die and an external die, means effecting nonrotational relative motion between said dies to effect cooperative internal and external shaping and curling of the brim of the lowermost cup disposed therebetween, and means adapted to engage said yieldable means for transferring the cup stack support function from said yieldable means directly to said dies during brim curling of said lowermost cup of said stack.
 2. The brim-curling apparatus of claim 1 wherein said yieldable supporting means comprise a plurality of dogs mounted in said frame for outward yielding movement, said dogs being disposed in circumferential array normally to engage beneath the lowermost cup of the stack, and said means for effecting nonrotational relative motion includes means mounting said internal die for axial movement to and from the open lowermost cup mouth and through said dog array thereby to deflect said dogs outwardly.
 3. The brim-curling apparatus of claim 2 including cooperating cam means between said internal die and said external die for effecting external die movement in response to axial movement of said internal die.
 4. The brim-curling apparatus of claim 3 wherein said external die comprises a pair of semicircular die portions disposed in normally laterally spaced relation to each other and to the lowermost stacked cup supported by said dogs, and, said cam means effects advancing confronting movement of said semicircular die portions into embracing brim-shaping relation about the cup periphery as said internal die enters the cup mouth.
 5. The brim-curling apparatus of claim 4 wherein said internal die includes cup-holding means to retain the cup thereon during brim curling thereof.
 6. The brim-curling apparatus of claim 5 wherein said cup-holding means is effective to remove the finished lowermost cup from the stack upon axial movement of said internal die from the stack.
 7. The brim-curling apparatus of claim 6 wherein said cup-holding means comprises a suction line acting through said internal die.
 8. The brim-curling apparatus of claim 7 including means to eject a finished cup from said die.
 9. The brim-curling apparatus of claim 6 wherein said cam means causes said external die portions to engage and support said cup stack during initial axial movement of said internal die and said finished cup thereon away from said stack.
 10. The brim-curling apparatus of claim 4 wherein said internal die is mounted on a crosshead having guide pins slidably journaled in said frame, and, said cam means are cooperatively associated with said external die portions and said guide pins. 